In preparing our new crotyl 1-methyl-butyl thiobarbituric acid, it is important that the crotyl halide (preferably bromide or chloride) used in preparing the crotyl 1-methyl-butyl ethylmalonate or the croytl 1-methyl-butyl ethylcyanacetate from which the desired crotyl 1-methyl-butyl thiobarbituri...
by hydrolytic cleavage of the acetal or acylate, more especially in the preparation of 4,4-dimethoxy-3-methyl-crotyl acetate, the yield is improved by carrying out the rearrangement in the presence of copper (I) chloride as the catalyst and ensuring that low-boiling by-products formed during ...
In preparing our new crotyl 1-methyl-propyl thiobarbituric acid, it is important that the crotyl halide (preferably bromide or chloride) used in preparing the crotyl 1-methyl-propyl ethylmalonate or the crotyl 1-methyl-propyl ethylcyanacetate from which the desired crotyl 1-methyl-propyl thiobarbit...